We studied at necropsy 18 patients (aged 38 to 73 years [mean 58]; 16 [89%] men) with chronic congestive heart failure (CHF) of greather 3 months duration, greather 75% cross-sectional area (XSA) narrowing of greather 1 of the 4 major epicardial coronary arteries by atherosclerotic plaque, and no flet ventricular (LV) fibrosis or necrosis. Because grossly visible myocardial lesions were absent, the severe chronic CHF in these 18 patients cannot reasonably be attributed to CAD. It is most reasonable to believe that this group of patients had idiopathic dilated cardiomyopathy and the CAD was coincidental.